The present invention is directed to the analysis of internal tissue of a patient. More particularly the present invention regards the use of a vacuum within a patient""s body to secure tissue near a diagnostic sensor.
Diagnostic procedures to analyze and diagnose a patient are a common component of modern medical care. There are numerous diagnostic procedures that can be performed on a patient. Some of these diagnostic procedures, such as x-ray and Magnetic Resonance Imaging, are performed completely outside of the body while others, such as tissue biopsies and in situ analysis, require entry into the body and more direct contact with the suspect body part. Those procedures that require more direct tissue contact may be performed through the esophagus and other existing orifices in the patient or through incisions, both small and large, made in the body of the patient.
Whether the diagnostic procedure is performed through an existing orifice or through an incision in the body of the patient, the tissue to be analyzed may often be out of the direct reach of the practitioner. In these situations, in order to reach and analyze the tissue, the practitioner will often employ an instrument having sensors at its distal end. When an instrument is employed the practitioner must manipulate and guide the instrument from outside the body in order to position the sensors, located at its distal end, next to the suspect tissue. This manipulation and steering of the instrument is often a time-consuming and cumbersome process.
For example, when tissue is analyzed during an endoluminal procedure, the practitioner must manipulate the medical instrument containing the sensor within the tight quarters of the endoscope. Once the sensor is properly positioned by the practitioner, it must then be maintained adjacent to the tissue in order to receive satisfactory results. In some circumstances the practitioner may not be able to satisfactorily manipulate the sensor in order to position it near the tissue to be analyzed. Similarly they may not be able to satisfactorily maintain the contact between the tissue and the instrument during the analysis. To resolve both of these problems, a second instrument, having a hook at its distal end, has been employed. This second instrument is inserted down into the endoscope in order to hook the tissue, move it next to the sensor, and hold the tissue in place during the testing. The application of this second instrument, although frequently used, is disfavored as its use is time consuming and can injure and permanently damage the tissue being tested.
In another example, when diagnostic testing is performed without an endoscope, directly through an incision into the patient""s body, the practitioner must also position the sensor adjacent to the suspect tissue and may also be required to hold the tissue in direct contact with the catheter in order to perform the analysis. Here, too, positioning the catheter and maintaining its direct contact with the tissue is an arduous and tedious process. A second instrument, such as the hook described above, is often used to grab the tissue, tug it to the sensor and anchor the tissue in direct contact with the catheter. As in the endoluminal procedure, the use of this second instrument, the hook, prolongs the procedure and increases the risk of injury to the tissue.
As is evident, what is needed is a method and an apparatus that provides for the diagnosis of suspect and diseased tissue within the body of a patient without the cumbersome, time-consuming, and risky procedures that have been employed in the past.
In accordance with the present invention a diagnostic catheter using a vacuum for tissue positioning is provided. A method for analyzing tissue in accordance with one embodiment of the present invention includes inserting a catheter having a sensor at its distal end into the body of a patient. Applying suction through the catheter to draw tissue into a predetermined sensing position and then analyzing the tissue with the sensor.
An apparatus for testing tissue within the body of a patient in accordance with an alternative embodiment of the present invention is also provided. This alternative embodiment includes a catheter having a first end and a second end, the first end having an orifice and also having a sensor, the orifice in fluid communication with a vacuum channel.